Geared type-bar action mechanism for typewriters



n- 12, 1932- M. GARBELL GEARED TYPE BAR ACTION MECHANISM FOR TYPEWRITERS Filed Dec. 5. 1927 2 Sheets-Sheet 12, 1932. M, ARBELL' 1,841,112

GEARED TYPE BAR ACTION MECHANISM FOR TYPEWRITERS Filed Dec. 5. 1927 2 Sheets-Sheet 2 an wa Patented Jan. 12, 1932 UNITED STATES PATENT MAX GARBELL, OF CHICAGO, ILLINOIS, ASSIGNOR TO VICTOR ADDENG magmas COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 0173 ILLINOIS GEARED TYPE-BAR ACTION MECHANISM FOR TYPE Application filed December 5, 1927.

The present invention relates to type-action mechanisms for typewriting machines, and has for one of its primary objects the construction of such type-bar act ion mechanisms that are easy to assemble, simple in construction, and which will afi'ord a snappy and lively printing action when employed on typewriting machines, especially such as have a top-strike type of platen. A further object of my invention is to provide type-bar actions of simple form and outline, so that they may be readily manufactured by the usual stamping and forming operations, as for example on a punch-press or the like.

A further object of my invention is to provide a type-bar which is actuated by means of a gear and a gear-rack, and which is so constructed that the speed of the type-bar will be accelerated near the end of the stroke so that the printing action will be lively and rapid.

Still further objects of my present invention will appear in connection with the description and the drawings which form a part of the present specification.

In the drawings, Figure 1 is a side elevational view of the essential elements of my improved type-bar action mechanism;

Fig. 2 is a similar view of a modification of my improved type-bar action mechanism; and

Figs. 3, 4, and 5 are likewise side elevational views of still further modifications of my improved type-bar action mechanism.

The essential feature of my invention lies in the use of gears for actuating the type-baron the depression of the key-lever, any intermediate links used in the various combinations and modifications being interconnected by means of gears, as contrasted with the employment of links, rods and the like.

In each of the modifications shown on the aforesaid drawings, it will be seen that I have provided a gear segment on the key lever, as well as gear segments on the intermediate lever; though, in some cases, as in Figs. 4 and 5, only a single tooth of. a gear is employed on the key-lever and a single interdental space on one end of the intermediate lever.

Serial No. 237,685.

Suitable means, such as springs, are also provided to retract the type-bar, the keylever, or the intermediate lever, the object in every case being to return the type-bar and associated mechanism to their original position at the beginning of the stroke.

Referring to Fig. l of the hereunto annexed drawings, which is a side elevational View of one modification of my improved type-bar action mechanism, it will be seen that there is provided a type-bar l which is pivoted at one end thereof by a pivot 2 and which is provided with a plurality of gearteeth 3 at said pivoted end. This type-bar also carries two or more type characters 1 at the free end thereof and located in such manner that when the said type-bar 1 is actuated it will strike between the side and the top of a platen 5, thus forming what is commonly known in the typewriter art as a top strike action. The line of travel of the free end of said type-bar is indicated upon the drawing by dotted lines.

The type-bar 1 is caused to swing upon its pivot 2 by the downward movement of a gearrack 6 which in the present exemplification of my invention is arranged on the free end of the intermediate lever 7. This lever is prac tically in the form of a right angle and is pivoted by means of a suitable pin 8 near one end, as shown in the drawings Fig. 1, and is also provided with gear-teeth 9. The keylever 10, of which only a portion is shown in Fig. 1, is pivoted by a pin 11 and is provided with gear-teeth 12 which are in intermcshing relationship with the gear-teeth 9 on the intermediate lever 7. A compression spring 13 serves to keep the key-lever in its normal horizontal position.

The operation of the above described mechanism is as follows: when-the key-lever 10 is depressed, it will swing upon its pivot 11 so that the intermeshing gears 9 and 12 will be caused to move, the gear 12 moving upwardly, and, in turn, pushing the gear 9 in a similar direction, as a result of which action the intermediate lever 7 will be caused to swing upon its oivot 8 thereby causing the gear-rack 6 to move downwardly. Inasmuch as the gear-rack 6 engages the gears 3 on the typebar 1, the type-bar will be swung on its pivot 2 and the type characters 4 will be caused to strike the platen 5, either directly or through a suitable printing-ribbon, as shown on the drawings.

By virtue of the movement of the intermediate lever 7 about its pivot 8, the rack 6 will move downwardly in an arc of a circle which has its center at the pivot 8, and for this reason the gear-teeth on the are 6 are on a pitch line which is of the same radius as the arc of which 8 is the center, thus keeping the gear-teeth on the rack 6 and on the gear 3 in intermeshing engagement throughout the stroke of the type-bar.

The universal bar 7?) that serves to actuate the carriage escapement mechanism is operated by contacting with the lower side of the intermediate lever 7 on its down stroke, a similar universal bar (not shown) serving to actuate the ribbon mechanism. If it should be desired to have so called dead keys on the typewriter, this is provided for by cutting a recess 7 a (shown in dotted lines) into the intermediate lever 7 so that the universal bar 7?) that operates the carriage escapement.

mechanism will enter said recess 7 wand thus remain motionless. The universal bar that operates the ribbon mechanism, being located either in front of or behind the universal bar 7 b will, however, be operated as usual.

It will be seen that in this construction I have provided a type-bar mechanism of extreme simplicity as the type-bars, intermediate lever, and key lever are all of such shape that they may be readily manufactured by stamping from sheet metal and also may have rods as pivots, being kept in place by slots in the usual type of segment, such as is known in the .typewriter art. This type of con struction also simplifies the assembly of the mechanism, thus lowering the cost of constructing typewriting machines which incorporate my present improvements.

A modlfication of the general type of construction shown in Fig. 1 is shown by Fig. 2. Referring now to this figure (Fig. 2), it will be seen that I have provided a type bar 1 which swings about a pivot 2 and has gearteeth 3 at the pivot 2 thereof and type characters 4 at its free end, so arranged that they may strike near the upper part of the platen 5 in exactly the same way as in Fig. 1. The gear-rack 6 arranged on an intermediate lever 7 performs the same functions as the gear-rack 6 shown in Fig. 1. It should be noted, however, that the intermediate lever 7 in Fig. 2 has a different shape from that shown in Fig. 1. It is, however, pivoted at 8 and is provided with a gearrack 9 which performs a similar function to the gear 9 of Fig. 1. The key lever 10 in Fig. 2 is pivoted at one end thereof, being provided with an extension 11 having a hole 11a, serving as the pivot. A compression spring 13 serves to return the key lever to its normal position.

A. universal bar 7?) may be provided and actuated by contact with the bottom of intermediate lever 7 on its downward stroke, and the said intermediate lever may be provided with a suitable recess 7a (shown in dotted lines) if a dead key construction is de sired. This will function in the same man ner as described in connection with Fig. 1.

The operation of the mechanism shown in Fig. 2 is as follows: (hen the key lever 10 is depressed it will cause a downward movement of the gear-rack 9 on the intermediate lever 7 which, in turn, will cause a downward movement of the rack 6 so that the type-bar 1 will be propelled toward the platen and will be caused to strike the same in a similar manner to that shown in Fig. 1. What has been said regarding the shape of the rack 6, byreason of the action of said rack being on an arc of a circle the center of which is at the pivot 8, as in F ig'. 1, also applies to the construction as shown in Fig. 2. It will be seen that in the construction, as shown in Fig. 2, I have provided a novel and comparatively simple form of type-bar action which readily permits itself to assembly and the parts of which are capable of being manufactured by stamping operations and which may be assembled upon pivotal rods by assembling the type-bars and intermediate levers on suitable segments as is well understood in the art of typewriter construction.

Fig. 3 shows a simplified form of con.- struction of my improved type-bar action mechanism in accordance with my present invention.

For this purpose I provide a type-bar 1 pivoted by means of a pivot 2 at one end thereof, and having a number of gear-teeth 3 at said pivoted end, and type characters 4 upon the free end of said type-bar and capable of striking a platenb near the upper part thereof, in the same manner as has already been described in connection with Figs. 1 and 2. I also provide the key-lever 10, which is in the present modification pivoted at its end on the in 11 and is provided near the center thereof, with a gear-rack 6 which is vertically disposed, and of such shape and dimensions that the gears of said rack 6 will be in intermeshing relationship with the gears upon the type-bar 1 throughout the travel of said type-bar from its position at rest to the time it strikes the platen. A suitable spring 13 is provided to return the key-lever 10 to the position which it has at the beginning of the stroke. It willbe noticed that in this form of type-bar action, I have completely eliminated the use of any intermediate levers so that the assembly of this type-ha r action will be extremely simple. In order to show more clearly the operation of this mechanism, the position of the key-lever 10 and versal bars that actuate the ribbon and the carriage escapement mechanisms, extensions 10a and 10?) on the key-lever 10 are provided. These extensions contact with and depress the universal bars 100 and 10d when the key-lever 10 is depressed. In order to provide a dead key construction, it suflices to omit one or'the other of the said extensions 10a and 10?), so that the desired universal bar will not be operated. It is usual, in the construction adapted by me in accordance with my present invention, to make the dead key by omitting onl the extension that actuates the universal bar releasing the carriage escapement mechanism, as it'is necessary to operate the ribbon mechanism .in all cases. In Fig. 3, either bar 100 or 1003 may be the universal bar that operates the carriage escapement mechanism.

The operation of this form of mechanism is as follows: On depressing the key-lever 10, the rack 6 will be propelled downwardly and by reason of this intermeshing engagement with 'the gears 3 and the pivoted end'of the type-bar 1 will cause the said bar to swing upon its pivot 2 and strike the platen 5, returning to its original position when the key-lever 10 is released. As in the other figures already described, the rack 6 will move on an arc of a circle whose center isat 11 and for this reason the rack should have such a shape that it will be in constant engagement with the teeth on the type-bar 1 throughout the stroke. The operation of extensions 10a and 106 has already been described.

It will be noted that in this type of construction, I have provided an extremely simple form of type-bar mechanism which requires only two pivots and has only two moving parts'so that the same will be very inexpensive and be very easy to assemble into a t pewriting machine.

other modification of my present invention is exemplified by the construction shown in Fig. 4. The usual type bar 1 hinged upon its pivot 2 on one end thereof and provided with gear-teeth 3-and type characters 4 so arranged as to strike near the topof a platen 5 is of a construction spbstantially the same as shown in the other figures already described herein. An intermediate lever 7 having a gear-rack 6, which latter is in intermeshing relationship with the gears 3 on the pivoted end of the type-bar 1, is hinged at its end upon the pivot 8. This intermediate lever 7 is provided with a slot 14 having an enlargement 15 toward the pivoted end of the said lever 7. In place of the key-levers shown in the other figures, I here provide a key-plunger a which works in a vertical direction within slots 16 and 16a made in a suitable material 17, which may be either metal or may be a molded composition, the slots and type-plunger being so proportioned that the said type-plunger will be kept in vertical alignment when depressed, a tension spring 13 serving to restrain and to retract the said type-plunger into its original position after having been depressed. The keyplunger 10a has a lateral extending curved arm 18 provided at its extremity with a roller 19 which is in engagement with the aforesaid slot 14, being assembled into its slot by being pushed through the enlargement of the slot 14. It should be noticed that in this .construction the roller 19 on the key-lever acts as would a single tooth on a rack or gear segment, and the slot 14 performs the same function as would an interdental space in a suitable gear intermeshing with said tooth, the gear in this case having its center at the pivotal point 8.

It will be seen that I have provided in this type of construction, a simple type-action mechanism that is operated by the depression of a key-plunger and which requires only two ivotal points, and the parts of which readily lend themselves to manufacture by stamping operations, and which will readily and cheaply be assembled in a typewriter.

The operation of the mechanism constructed as shown and described in connection with Fig. 4 is as follows: When the key-plunger 10a is depressed, the intermediate lever 7 will be pushed downwardly by reason of the interaction between the roller 19 on the lateral arm of the key-plunger 10a, thus causing a downward movement of the rack 6 at the free end of the intermediate lever 7, which latter, by virtue of its intermeshing engagement with the gears 3 on the pivoted end of the type-bar 1, will cause the same toswmg upon its pivot 8 to strike the platen 5.

The pitch line of the gears on the rack 6 lie upon the arc of a circle the center of which is at the center of the pivot 8 so as to insure the engagement of the teeth 6 and 3 throughout the stroke.

Still a further modification of my present invention is shown in Fig. 5. The type-bar 1 and its associated type-characters, gears and pivots are substantially the same as shown in the other drawings and need not, therefore, be further described. The intermediate lever 7 with the rack 6 thereof is substantially in the shape of a right angle but instead of being pivoted at its end, as in Figs. 1, 2 and 4, is, in this modification of my construction, in the form of a bell-crank which oscillates about the pivot 8, and is provided at the end opposite to where rack 6 is located with a slot 14a which is formedby making the ends of the said bell-crank 7 bifurcate.

v A key-lever 10, which, in this form of construction, is pivoted and oscillates about a pin 11 located along its-length at a suitable point, is provided at its end with a pin or roller 19a, which is in engagement with the aforesaid slot 14a in the bell-crank 7. A suitable spring 13 is provided to insure the return of the bifurcate end of the bell-crank 7 into substantially horizontal position such as it has had at the beginning of a type-stroke. Mechanically, this construction is the equivalent of that shown in Fig l, the roller or pin 19a (in Fig.5) being equivalent to the gears 12 on the key-lever in Fig. 1,, and the slot 14a (Fig. 5) formed by-the bifurcate end of the intermediate lever is equivalent to an inter-dental space in the gears 9 on the intermediate lever (in Fig. 1).

Similar provisions for forming dead keys as described in connection with Figs. 1 and 2 may be made in the construction shown in Figs. 4 and 5, namely by forming suitably shaped recesses 7a to allow of the entrance of an universal bar 7?).

It will be seen thatin this form of construction, I have provided an extremely simple form of type action mechanism and one that readily lends itself to manufacturing operations such as stamping, and which is easily and cheaply assembled and the parts of which, especially the bell-crank 7 may be made comparatively small so that a typewriter incorporating my new improved mechanism may be made of relatively small dimensions.

Operation of the mechanism shown in Fig. 5 is as follows: \Vhen the key-lever 10 is depressed, it will swing upon its pivot 11 so that the rearward end of the said key-lever will move upwardly thus, in turn, moving the forward end of the bell-crank 7 upwardly by reason of the slidable engagement of the pin or roller 19a with the slot 14a, causing the bell-crank 7 to oscillate upon its pivot 8 so that the rack 6 will move in a downwardly direction. It is also necessary in this form of construction, that the pitch line of the gear-rack 6 be either so positioned that it lies upon the are of a circle, the center of which is at 8, or, alternatively, that the type-bar 1 be pivoted at a point other than its center, so that intermeshing relationship may be main tained between the gear-rack 6 and the gears 3.

I Other modifications of my herein described forms of construction which are within the skill of an ordinary mechanic are to be understood as coming within the scope of my herein described invention. I do not desire to be limited by the precise construction shown herein, but wish to be bound only by the scope of the hereunto appended claims as they may be viewed in connection with the prior art.

What I claim as new and desire to be pro tected by Letters Patent of the United States is as follows:

1. In a type-bar action mechanism for typewriters, the combination of a type-bar, an intermediate lever, and a key lever, a multiple-toothed gear element on said type-bar, two multipletoothed gear elements on said intermediate lever, and a multiple-toothed gear element on said key lever, one of the gear elements on said intermediate lever intermeshing with the gear element on said typebar and the other of the gear elements on said intermediate lever intermeshing with the gear element on said key lever at points of contact substantially in alignment with the pivots of said key lever and intermediate lever throughout the movements of said levers.

2. In a type-bar action mechanism for typewriters, the combination of a type-bar having a set of gear teeth at its pivoted end, an intermediate lever having gear teeth at its free end and at its pivoted end, and a key lever having gear teeth at its pivoted end, the gears on said type-bar intermeshing with the gears on the free end of the intermediate lever, and the gears on the key-lever intermeshing with the gears on the pivoted end of said intermediate lever between the pivots of said key lever and intermediate lever and sub stantially in alignment with said pivots.

3. In a type-bar action mechanism for typewriters, the combination of a key-lever pivoted near one end and having gear teeth at said end, an intermediate lever having gears at both ends and a pivot at one end, and a type-bar having gears at its pivoted end, the gears on said type-bar intermeshing with one set of gears on said intermediate lever, and thegears on said key-lever intermeshing with the other set of gears on said intermediate lever between the pivots of said hey lever and intermediate lever and substantially in alignment with said pivots.

4. In a type-bar action mechanism for typewriters, the combination of a type-bar pivoted at one end and having gear teeth at said end, an intermediate lever having gears at both its free and its pivoted ends, and a pivoted key-lever having gears at one end intermeshing with the gears on the pivoted end of said intermediate lever between the pivots of said key lever and intermediate lever and substantially in alignment with said pivots.

5. In a type-bar action mechanism for typewriters, the combination of a type-bar pivoted near one end, gears on said type-bar at its pivoted end, an intermediate lever having gears at its pivoted and its free end, said gears on the free end thereof intermeshing with the gears on said type-bar and a keylever having gears on one end intermeshing with the gears on the pivoted end of said intermediate' lever between the pivots of said key lever and intermediate lever, and substantially in alignment with said pivots.

6. In a type-bar action mechanism for typewriters, the combination of a type-bar pivoted near one end thereof and having gear teeth at said end, a pivoted intermediate lever bifurcate at one end and having gear teeth at the other end in intermeshing relationship with the gear teeth on the said typebar, and a pivoted'key-lever having a pin and roller at'one end, said roller being in engagement with the bifurcate end of the said intermediate lever and being located between the pivots of said intermediate lever and said key-lever.

7. In a type-bar action mechanism for typewriters, the combination of a type-bar pivoted near one end thereof and having gear teeth at said end, an intermediate lever in the form of a bell-crank bifurcate at one end and provided with gear teeth at the other end in intermeshing relationship with the gear teeth on said type-bar, a pivoted key-lever, and a pin and roller at one end of said keylever, said roller being in engagement with the bifurcate end of said intermediate lever and being located between the pivots of said intermediate lever and said key-lever.

8. In a type-bar action mechanism for typewriters, the combination of a pivoted key-lever having a pin at one end, a roller on said pin, a bell-crank having a slot at one end engaging said roller and having gear teeth at the other end, a type-bar pivoted near one end and having gear teeth at said end 1n engagement with the gear teeth on said bell-crank, and means, comprising a spr ng, for returning the mechanism to its initial position after a stroke, said slot-androller connection between said key-lever and said bell-crank being located between the p votsof the latter two members and substantially 1n alignment with said pivots.

9. In a type-bar action, a pivoted type-bar havlng a multiple-toothed gear element, an lntermediate lever having two multipletoothed gear elements, and a key-lever havmg a multiple-toothed gfir element, said gear elements intermeshing to form a train of gears interconnecting said type-bar and key-lever and intermeshing at points of contact substantially in alignment with the pivots of the members carrying the respective gear elements throughout the movements of said members.

10. In a type-bar action mechanism for typewriters, the combination of a key-lever having a pin at one end thereof, a roller on said pin, an intermediate lever having a slot at one end thereof engaged by said roller and having gear teeth at the other end thereof, and a type-bar pivoted near one end thereof and having gear teeth at said end in engagement with the gear'teeth of said intermediatelever, said key-lever and intermediate lever being pivotally supported at points in substantially horizontal alignment, and the slot-and-roller connection between said keylever and intermediate lever being located between said points and substantially in alignment therewith.

11. Ina type-bar action mechanism for typewriters, the combination of a pivoted key-lever, a pivoted intermediate lever having gear teeth at one end thereof, means forming a toothed connection between the other end of said intermediate lever and one end of said key-lever, and a type-bar pivoted near one end thereof and having gear teeth at said end intermeshing with the gear teeth of said intermediate lever, said toothed connection between said intermediate lever and said rev-lever being located between the pivot points of said levers and substantially in alignment with said pivot points.

12. Ina type-bar action mechanism for typewriters, the combination of a pivoted key-lever, a pivoted intermediate lever having gear teeth at one end thereof, means forming a toothed connection between the other end of said intermediate lever and one end of said key-lever, and a type-bar pivoted near one end thereof and having gear teeth at said end intermeshing with the gear teeth of said intermediate lever, the pivot points of said intermediate lever and said key-lever being located in' substantially horizontal alignment with each other, and the toothed connection between said levers being located between said pivot points and substantially in alignment therewith.

In witness whereof, I have hereunto subscribed my name.

MAX GARBELL. 

